Any pump you put in that well is going to need a 2 or 3 GPM Dole valve or ball valve choking it back to keep from pumping the well dry. So you could use the pump you have now, just need to reduce its flow to less than 3 GPM. Or you could use that deep well pump in the cistern to pump water to the house and get a new 5 GPM, 1/2 HP to put in the well. The 1/2 HP AY McDonald you mentioned will not give more than 50 PSI. You need to run at 60/80 to get 70 PSI to the house, since you want 55 PSI and you have 40' rise, which equals 70 PSI. Oh, and you only need a 4.4 gallon pressure tank if you use a CSV.